Call, Josep Department of Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, Max Planck Society;
Cacchione, T., & Call, J. (2010). Intuitions about gravity and solidity in great apes: the tubes task. Developmental Science, 13(2), 320-330. doi:10.1111/j.1467-7687.2009.00881.x.